There have been many approaches to removing accidental image oscillations which appear in optical viewing devices with the use of gyroscopes. Some efforts have been made to incorporate massive wheels into the instrument housing for brute force stabilization. These devices make a valiant effort at first, but soon become unwieldly and confusing to the operator. The principal endeavor thus far in the art has been directed toward space stabilizing an optic element with the aid of the classic two-degree-of-freedom or "free" gyro. This consists, in the main, of a member housing the wheel surrounded by a gimbal that contains two axes orthogonal to the spin axis of stabilization about either or both of the latter two or gimbal axes. In all instances where reference is made to the stabilizing mechanism as a compartment called "stabilizer" or other similar connotation, the free gyro is understood. This approach to image stabilization entails a rather large and cumbersome mechanism requiring special assembly techniques to exact a close balance of several members and also requiring a friction-free condition at gimbal support bearings. Power for motivation is supplied by the angular momentum of the wheel whose space reference is subject to drift in less than one minute's time. Moreover, lens system must usually be added and optic paths are interrupted in unseemly fashion. Also, in some cases, a two-degree-of-freedom assembly is included for each separate axis to be stabilized in order to avoid the effects of cross coupling. Finally, in slaving a free gyro back to its neutral position relative to the case, all manner of complicated erection systems must be invented.
The present invention proposes to mount one or more of the reflectors which are needed to invert or reverse the image onto pivots and add alongside a small gyro for coupling thereto. This gyro is the single-degree-of-freedom type, having only one gimbal or output axis extending from the spin wheel housing. Further objects intended include that a typical embodiment from the invention would:
(1) Offer mechanical compensation directly in the form of a positive shaft rotation. PA0 (2) Manipulate the stabilizing element without interrupting or otherwise interfering with the optic path. PA0 (3) Incorporate simple slaving means with classic rate gyro mode. PA0 (4) Add only a few, if any, optic components to those already needed in the system before stabilization. PA0 (5) Be very beneficial to photo cameras.